Vallaint 615 - Wiring Guidance with External Frost Stat

[billy0liar]

Hi to all can any one assist ?

System
Vallaint 615 system Boiler
Auro STOR 210 Ltr Solar Cylinder

I have contacted Valliant regards intergrating a separate frost stat into my system design, they have told me that nothing is on offer that is compatible with their EBus System, I am guessing no low voltage stat.

They have suggested utilising external controls...therefore, I am proposing to use a Honeywell S plan with the following...

ST9400C1000 - Programmer 7 day - 2 channel
2 X Honeywell 2 Ports
1 Honeywell Room Stat T6360
1 x Honey Well Frost Stat 4360

I have utilised an attached outhouse to locate the cylinder in, dry lined it and insulated with kingspan, double glazed the door. I want to locate the frost stat in the out house just in case the second ice age comes on 21/12/2012.

My question, its been a while since I wired a S Plan to a complexed boiler, usually combis are straight forward and preprogrammed with pump over run and other clever stuff. How do I take account of the pump over run requirement in terms of controlling the boiler by external controls, i.e. if the 2 port breaks the supply to the boiler when the stats are satisfied ? Is there clever technology in the pcb that will keep the pump running, which I assume requires another permanent supply to the boiler ???

Any guidance welcome....

 

[simond]

All sorts of info are missing from this post.

Where is the boiler being sited? In the outhouse you describe or elsewhere?

If the boiler is in the outhouse, then the internal 2 stage boiler protection will look after things.

If not, then you have to use your own controls as Vaillant suggest. If you are a boiler installer this should be simple, if you aren't then my first question would be 'why are you installing regulated appliances - unvented and gas boiler - when you are not trained and approved?'

The best way to connect frost protection is to use a Honeywell frost protection kit, comprising a pipe and wall stat.

The new Vaillant ecoTEC MkIIs have a single input, RT, for the switched live. Other than that, you just need to follow a standard s plan and add the frost stat.

Or employ a professional.

 

[Agile]

The boiler should always have a permanent live and then it can provide frost protection based on the temperature where the boiler is installed.

Because a cylinder is expected to be warm and not at risk of freezing it would be unusual to fit a frost stat at the cylinder but if you thought it likely to be left cold during cold weather then one could be added to heat up the cylinder if the tank room became too cold.

I hope you remember the auto bypass!

Tony

 

[billy0liar]

Thanks to all for the replies.
As stated the "cylinder" is in the outhouse
The boiler is inside the property. Trained as
A plumber 20 years ago, so I class myself
As compentant and the system will be in
My own property. I already know the boiler
Has a frost stat in it. The frost stat is to be situated
In the outhouse which is fully insulated, and I
Intend to utilise the frost stat that has no
Sensor on the return pipework as that does
Not necessarily Gaurentee that my outhouse
Will be protected from freezing just because
The return pipes warm !!

I need to read the lit on the 615 again, as I believe
It incorporates an auto bypass anyway, plus i have a bypass
Rad with no trvs situated in the room with
Stat.

It would be useful to understand the science of how the wiring config
Works for the pump overrun, if in deed it actually can ?
Thanks again

 

[billy0liar]

Thanks to all for the replies.
As stated the "cylinder" is in the outhouse
The boiler is inside the property. Trained as
A plumber 20 years ago, so I class myself
As compentant and the system will be in
My own property. I already know the boiler
Has a frost stat in it. The frost stat is to be situated
In the outhouse which is fully insulated, and I
Intend to utilise the frost stat that has no
Sensor on the return pipework as that does
Not necessarily Gaurentee that my outhouse
Will be protected from freezing just because
The return pipes warm !!

I need to read the lit on the 615 again, as I believe
It incorporates an auto bypass anyway, plus i have a bypass
Rad with no trvs situated in the room with
Stat.

It would be useful to understand the science of how the wiring config
Works for the pump overrun, if in deed it actually can ?
Thanks again

 

[Agile]

The boiler does have a built in bypass but thats only for the protection of the boiler itself and an external auto bypass should always be fitted.

Using a rad is no longer permitted as all rads should now have TRVs.

Tony